Where does your charging come from survey

[booster]

Originally Posted by VanFan

Starting with 100% state of charge in the morning, our normal daily use is about 90 amps. That's without even thinking about power conservation. Cooking with a microwave, making coffee, watching television for 2 or 3 hours in the evening, etc.

Our van is designed with a door to close off the sleeping area where the AC unit and the thermostat are, so we're actually only cooling half of the van when we sleep. Because of that arrangement, the AC only draws about 70 amps per hour since the compressor cycles off more than usual. (It's 90 amps with the compressor on.) The inverter and phantom loads are another 5 or so, which leaves about 120-140 amps for charging when the AC is running and the alternators are combined.

With a full battery at bedtime, our auto-start system is set to start the engine when the state of charge drops to 20%. That usually takes about 5.5 to 6 hours. Then while we're still asleep the engine runs for one hour (maximum auto-start system time) which delivers another 120 amps to the battery (the AC is still cooling). Then we get another 1.5 hours or so on battery alone, which gets us our 8 hours of sleep. We wake up with enough power for breakfast and coffee, then we have to either drive or idle to recharge. Takes about 2.5 hours to get back up to 100% SOC from 20% at idle with no loads.

So our worst case power usage is about 730 amps per day while boondocking in the Texas summer, idling the engine about 4.5 hours per day (burns about 2 gallons of gas). The rest of the year it's about 90 amps of use and less than an hour of idle time. In practice, when it's cool enough to sleep without the AC we could boondock for 5 days without running the engine. But we rarely stay anywhere more than two nights.

Would you be able to clarify which numbers are amps and which are amp hours, it is quite confusing, I fear.

[VanFan]

Just edited to hopefully make it more clear. Sorry about that.

[booster]

Originally Posted by VanFan

Just edited to hopefully make it more clear. Sorry about that.

Thank you, very much appreciated!

[PJ2016]

2012 Pleasure Way Plateau RB

100 ahr AGM & 375 ahr Lithium (two 125ahr Stark & one 125 ahr LithiumHub);
Two converters; 70 amp converter (PD9170L) & 45 amp converter (PD9245C)
2500 Onan lp generator;
No solar panels;
Domectic marine refrigerator (defoss compressor);

2kw Xantrex HF sine wave inverter, a built-in transfer switch powers everthing that is 120vac except the air conditioner when inverter is operating.

Dry camping only the 375 ahr lithiums are connected to the coach; 100 to 140 ahr per day (depending on microwave, convection oven, toaster, coffee maker and furnace use); No air conditioner when dry camping (it is not powered by the inverter)

On average I'll run the generator from 1 to 1-1/2 hours per day, with the two converters paralleled charge current starts at about 90 amps and tapers down to low 70's; we frequently leave the campground, charge current averages 40 amps while driving.

On shore power only the 100 ahr AGM & the 45A PD9245C are connected to the coach.

[Winston]

PERTINENT STATISTICS:
500ah Lithium
810 watts solar
Nations 2nd Alternator
Magnum 2812 - 125amps shore power charging

Would love to answer ‘The Question’ that initiated this thread, but the best we can do is say 'it depends'.

We're like Davydd . . . our inverter runs ‘all-the-time’ (except during shore power) and we like ‘toys’ . . . and use lots of power. Seems no day goes by without consuming at least 2.5kwh (~190ah). Often substantially more.

On a good sun day we can cover our consumption with solar - - we’ve posted many 4 kwh solar days with a peak solar day of, so far, 4.5kwh. On these days, we need no other charging source than solar The resulting numbers are:

Solar: 100%
Shore Power: 0%
2nd Alternator: 0%

But on those not-too-infrequent occasions when we get very minimal solar energy, shore power becomes our preferred alternative. It not only picks-up much of the load (thereby lowering that days kwh battery demand) but its 125 amp charge rate is more than sufficient to return the batteries to the desired State of Charge. On such a day:

Solar: 0%
Shore Power: 100%
2nd Alternator: 0%

But, alas, there are those days when we camp off-grid . . . with no shore power (and no sun). Now we must rely on the 2nd alternator. We prefer to run the 2nd alternator while running errands or relocating from one destination to another. But if required, we idle our gas ProMaster to get the job done. The numbers:

Solar: 0%
Shore Power: 0%
2nd Alternator: 100%

With these extremes we’re reluctant to assign overall percentages. What we’ve concluded is that we’re happy to have designed a system with all three charging sources - - each having, in our opinion, a time and place. And, yes, as Davydd and others have suggested, solar could be eliminated . . . but in the absence of carrying our kayaks on the roof . . . we so no need to drop this alternative energy source. After all, there have been those days while boon docking that the solar has sufficed and has eliminated our need to drive or otherwise ‘idle’ our 2nd alternator.

[booster]

It sounds like Winston has a "scaled up" version of what a lot of the others of us see in our systems, except we would have about 1/4-1/3 of the power use and solar. We would have similar alternator charging capacity and shore charging, though, and about 1/2 the battery capacity. Others do the same on 1/4 of his capacity though, also, without issue.


Very interesting and good information.

[InterBlog]

So how'd I do? Are you satisfied with the estimates that apply to your van?

There's some TL;DR in this thread that I had to skim in order to make a stab at deducing the rough usages.

[cruisefx]

Roadtrek 2004 190V

200 AH AGM
Solar 250W 80%
Alternator 20%
Shore 0%
Generator 0% (not installed)

2000W inverter
Using a Trimetric battery monitor, we can see that we rarely go below 75% state of charge. We do use the microwave, K-cup coffeemaker (3 times a day for 2), 12 v mini oven and Instant Pot. Instead of using the larger inverter, we also carry a 250W inverter that is used when watching TV or recharging devices. Travelled for 3 weeks to the Maritimes and never plugged in. Never used the air conditioner. Only use the Fantastic fan. Still have the 3-way fridge which will be on 12V when driving. Have tried using an induction cooktop.

We try to use high power usage items earlier in the day - i.e. cook dinner in the instant pot and then continue driving. So by the time the sun sets, we are still around 90% SOC.

[engnrsrule]

We have a 2006 Roadtrek Adventurous RS (Diesel Sprinter) with a generator. Just a little bit about our loads and AC configuration. The standard inverter is a modified sinewave type and has a 750W AC rating. When running on coach battery the inverter only powers one galley receptacle and the TV/DVD receptacle. We found that the upgraded TV does not tolerate modified sinewave feed, and neither does our Keurig, so the inverter is only used for charging phones or running the computer. We obviously cannot operate microwave or the Air Conditioner with this inverter. We run the generator when we need 110 AC to cool down the space or make coffee.

On a trip last summer we had a no shoretie campsite, and the propane option on our dometic fridge had stopped working. We were running on 12V but this drained our (85 Ah) coach battery beyond what we could maintain. The campground only allowed one hour of generator use which was insufficient. We got the propane option fixed and upgraded to two 235Ah 6V golf cart batteries which were the max we could fit in the existing battery compartment. We also installed a Victron battery monitor, which provided great insight into our usage.

We typically boondock a few nights when traveling and hopefully get a site (or friend's driveway) with shore tie at our destination.

So on to the question. Our recharging comes from either running the generator, running the engine, or from a small 6W solar panel we put on the dashboard (https://www.amazon.com/gp/product/B07DFCDKLJ/). Since increasing the battery capacity we have about 5-10 days of battery life. With conservative use plus the daily running of the generator to make coffee, and the small solar panel this goes to infinity. Also, we have found the most limiting system when boondocking is the black water tank. With two of us and no outside facility it has to be pumped out every 3-4 days. That requires running the engine for a bit. It is hard to put a percentage on it. But for a 10 day trip boondocking we would start out 100%, maybe use the generator for an hour a day, and keep the little solar panel on. Rely on engine to recharge as we find dump station every 3-4 days. That probably figures out to about half our charging from engine, 25% each from the generator and solar.

We are considering upgrading the inverter to support using the Keurig. That could be a bigger cost than just the inverter-charger, as the system is matched to the control panel, and only two outlets. We are not willing to give up any of the already limited storage to more batteries so are content with things for now.

[booster]

Originally Posted by engnrsrule

We have a 2006 Roadtrek Adventurous RS (Diesel Sprinter) with a generator. Just a little bit about our loads and AC configuration. The standard inverter is a modified sinewave type and has a 750W AC rating. When running on coach battery the inverter only powers one galley receptacle and the TV/DVD receptacle. We found that the upgraded TV does not tolerate modified sinewave feed, and neither does our Keurig, so the inverter is only used for charging phones or running the computer. We obviously cannot operate microwave or the Air Conditioner with this inverter. We run the generator when we need 110 AC to cool down the space or make coffee.

On a trip last summer we had a no shoretie campsite, and the propane option on our dometic fridge had stopped working. We were running on 12V but this drained our (85 Ah) coach battery beyond what we could maintain. The campground only allowed one hour of generator use which was insufficient. We got the propane option fixed and upgraded to two 235Ah 6V golf cart batteries which were the max we could fit in the existing battery compartment. We also installed a Victron battery monitor, which provided great insight into our usage.

We typically boondock a few nights when traveling and hopefully get a site (or friend's driveway) with shore tie at our destination.

So on to the question. Our recharging comes from either running the generator, running the engine, or from a small 6W solar panel we put on the dashboard (https://www.amazon.com/gp/product/B07DFCDKLJ/). Since increasing the battery capacity we have about 5-10 days of battery life. With conservative use plus the daily running of the generator to make coffee, and the small solar panel this goes to infinity. Also, we have found the most limiting system when boondocking is the black water tank. With two of us and no outside facility it has to be pumped out every 3-4 days. That requires running the engine for a bit. It is hard to put a percentage on it. But for a 10 day trip boondocking we would start out 100%, maybe use the generator for an hour a day, and keep the little solar panel on. Rely on engine to recharge as we find dump station every 3-4 days. That probably figures out to about half our charging from engine, 25% each from the generator and solar.

We are considering upgrading the inverter to support using the Keurig. That could be a bigger cost than just the inverter-charger, as the system is matched to the control panel, and only two outlets. We are not willing to give up any of the already limited storage to more batteries so are content with things for now.

From your description, and fairly common pattern of use, I think, my guess is that you are getting more charging from the alternator and generator than you think, as that 6w solar panel is only going to give you about 2ah per day max under good conditions. With a gas frig and no microwave or other high drain loads, even the TV not on batteries it appears, you probably have quite low power use in 20-30ah per day or so, as the lights would probably be you biggest loads, plus a little phone changing.


Since you have a monitor now, you certainly will get a better feel for things over time.



Sounds like it is time for an inverter upgrade, though. I assume you are using your home AC adapters for charging? It would be interesting to check and see if they are getting hotter than they do at home. I have heard from a couple of people that say the MSW inverters made their adapters run very hot. They didn't say if they were factory or aftermarket adapters, though, and we know some of the aftermarket stuff is pretty bad.

[engnrsrule]

Originally Posted by booster

From your description, and fairly common pattern of use, I think, my guess is that you are getting more charging from the alternator and generator than you think, as that 6w solar panel is only going to give you about 2ah per day max under good conditions. With a gas frig and no microwave or other high drain loads, even the TV not on batteries it appears, you probably have quite low power use in 20-30ah per day or so, as the lights would probably be you biggest loads, plus a little phone changing.


Since you have a monitor now, you certainly will get a better feel for things over time.



Sounds like it is time for an inverter upgrade, though. I assume you are using your home AC adapters for charging? It would be interesting to check and see if they are getting hotter than they do at home. I have heard from a couple of people that say the MSW inverters made their adapters run very hot. They didn't say if they were factory or aftermarket adapters, though, and we know some of the aftermarket stuff is pretty bad.

Thanks Booster - My concern with upgrade inverter is compatibility with existing RT control panel. But also thought I could put the Tripp Lite on charge only mode and just add a 2 or 3000 watt pure sine inverter. With that much power I would want to see power at all the outlets, not just the two now connected. Not sure how big a deal that change would be.
Will see about that

As for charging, I do not use the house chargers. I have a large power strip that has 6 USB outlets and I charge everything off that, or sometimes just charge the phones off a multi USB 12v accessory on a front socket and leave the inverter off, since it pulls an amp or so just being on. Charging off the engine battery at night doesn't seem to bother it at all.

[booster]

Originally Posted by engnrsrule

Thanks Booster - My concern with upgrade inverter is compatibility with existing RT control panel. But also thought I could put the Tripp Lite on charge only mode and just add a 2 or 3000 watt pure sine inverter. With that much power I would want to see power at all the outlets, not just the two now connected. Not sure how big a deal that change would be.
Will see about that

As for charging, I do not use the house chargers. I have a large power strip that has 6 USB outlets and I charge everything off that, or sometimes just charge the phones off a multi USB 12v accessory on a front socket and leave the inverter off, since it pulls an amp or so just being on. Charging off the engine battery at night doesn't seem to bother it at all.

Probably could use a new thread on an upgrade, but it can be done, as ours is that way, all outlets run on inverter or shore power and auto selected by the inverter charger. Rewiring is not horrible or terribly easy. The original panel will still work assuming you have the one with tanks and charge indicator lights and a separate inverter on switch, except for the inverter switch. A good inverter charger will also have it's own remote panel so the Roadtrek one gets relatively not used except for tanks.

[GeorgeRa]

Originally Posted by InterBlog

So how'd I do? Are you satisfied with the estimates that apply to your van?

There's some TL;DR in this thread that I had to skim in order to make a stab at deducing the rough usages.

32% solar, I think this number will continue to go up.

[skagitstan]

Originally Posted by booster

Buried in another, very contentious, thread on this forum is a question that I think would be interesting for many of us to better understand and for those contemplating charging system changes and upgrades to see from actual users.

The question is: What percent of your power comes from the various power sources available in our class b vans?

...

DIY on a Ford Transit 350 HR EL Ecoboost.

400AH AGM, 540W solar, BlueSea ACR, Magnum MS2012, and 30A shore.
Biggest load is the 7CF compressor fridge.



We start out with full charge from shore.
In the summer sun we can maintain charge indefinitely just on solar. This time of year we can go ~4-5 days before taking the batteries down to about 70%
Then driving a few hours to someplace new bring the batteries back up to float.


So I'd estimate we are probably about 70-80% sufficient just on solar.



At home, the shore keeps us in float whenever we are not out and about, and keeps an electric heater and dehumidifier running full time.

[tgregg]

Originally Posted by GeorgeRa

32% solar, I think this number will continue to go up.

For users with AGM / FLA batteries I agree with you because solar appears to be significant in reaching a full charge for AGM / FLA batteries.

But I think solar may become less of a factor as more users adopt Lithium batteries because the alternator can charge them faster than AGM / FLA and not fully charging Lithium batteries doesn't appear to harm them as much as it does AGM / FLA batteries.

I don't think I will ever spend money on solar charging for my RV and I believe I read that Davydd said his next ARV wouldn't include solar.

[booster]

Originally Posted by tgregg

For users with AGM / FLA batteries I agree with you because solar appears to be significant in reaching a full charge for AGM / FLA batteries.

But I think solar may become less of a factor as more users adopt Lithium batteries because the alternator can charge them faster than AGM / FLA and not fully charging Lithium batteries doesn't appear to harm them as much as it does AGM / FLA batteries.

I don't think I will ever spend money on solar charging for my RV and I believe I read that Davydd said his next ARV wouldn't include solar.

I think this is mostly true, but the lithiums have the cost penalty and also the cold weather handling issues, so it gets to be a balance. If your use pattern is compatible with the AGMs and solar, it is really seamless and rarely requires driving unless you are a big energy user. You also have to remember that up to about 80% SOC AGMs will charge just as fast as lithiums for the most part. You only need to get them all the way full periodically, so in quick recovery boondocking of the alternator. for a week or so, there is really not much difference, but then you would need on day of getting them full again before the next week. This fits many folks use profile so no penalty, but not everyone.

[GeorgeRa]

Originally Posted by tgregg

For users with AGM / FLA batteries I agree with you because solar appears to be significant in reaching a full charge for AGM / FLA batteries.

But I think solar may become less of a factor as more users adopt Lithium batteries because the alternator can charge them faster than AGM / FLA and not fully charging Lithium batteries doesn't appear to harm them as much as it does AGM / FLA batteries.

I don't think I will ever spend money on solar charging for my RV and I believe I read that Davydd said his next ARV wouldn't include solar.

Time will tell if energy demanding camping will prevail. For long distance cruising and live on board users you are perhaps correct, for comping folks like myself perhaps not.

[avanti]

A number of us have 440Ah AGMs. I think that this (with modest solar) is a sweet spot for anyone who uses significant power but doesn't aspire to all-night A/C. I almost never find myself wishing I had more power, and I am spared the complexity and hassles of Lithium.

[GallenH]

Interblog: Thanks!

[Davydd]

Lithium ion does not need to have a problem with cold weather handling issues if you understand them and know how to deal with them. From what I have read, it seems only ARV, has taken it seriously. It is just a matter of a little time for others to get with it.

I've said many times if you want a van that behaves electrically and transparently worry free with no compensating factors same as if you had shore power, lithium ion is the solution for now. The trend in boondocking which is much greater than when I got into RVing over a decade ago will drive it. You need not feel you have to be tethered to shore power.

That means a high amp hour storage solution that no AGM can touch because of weight limitations and space limitations. For instance to get the equivalent power from my 800ah lithium batteries you would need an impossible to accommodate or extremely impractical, 13 standard AGM batteries. You can nit pic and argue about what amp hour capacity you can achieve that, but the more you have the less worry and longer you can go. I assume a 3-4 day stationery stay for my criteria because traditionally before lithium that's about all we could tolerate before the itch to travel sets in or we have exhausted seeing and doing the area.

But once you have the amp hour capacity you are tasked with replenishment. Solar doesn't cut it as practical as a percentage of replacement to total battery capacity. That is the major reason why I am not going to get solar on my next Class B. The second alternator is way more efficient than solar, an Onan type generator or even shore power. The second alternator got off to a bad reputation with Roadtrek touting Voltstart and idling. Very few people I know, and I know perhaps more high amp lithium battery owners than the average, that users don't rely on idling. They drive like you are suppose to do like no other RV--that's the advantage of a Class B over other RVs. A half hour of driving will replenish more than the best sun conditions over a day. Other no brainer reasons.

1. My next van will be 5 foot shorter than my current Class B and I already know solar is not a big contributor in my current set up maxed out at 420 watts.

2. With a shorter van I have opted to have two skylights instead of one on top of everything else I currently have. So, I would only have a token amount than I have now which will do even less.

3. Though I haven't planned for it, there is a trend, especially adventure type vans, to utilize the roof for a deck with a ladder. I want to leave that option open for now. Other adventurers may opt to carry things like kayaks up on the roof.

4. We mostly travel in sunny unobstructed areas in fall, winter and spring where the days are short and the sun angles are low. In the summer we seek shade and the cooler north woods.

5. I now park inside a garage for storage when I don't use the van. No solar there.

The cost factor is real and will never come down to lead-acid levels, but it will come down. You get so many more advantages, and envy and expectations will change for Class B seekers, and they will readily absorb the cost.